Onion is a type of vegetable that belongs to the allium family, which also includes garlic, leeks, and chives. Onions are widely used in cooking around the world, as they add flavor and aroma to many different dishes. They come in various sizes and colors, including white, yellow, and red.

Onions are rich in antioxidants and are a good source of vitamin C, dietary fiber, and various minerals such as potassium, magnesium, and calcium. They also contain sulfur compounds, which are responsible for their pungent odor and may have health benefits.

Onions can be consumed raw or cooked and are used in many different types of dishes, such as soups, stews, salads, and sandwiches. They are also often used as a base ingredient for sauces and gravies.